Where Supergirl previously established its universe’s American President as Lynda Carter’s Olivia Marsdin (and apparently an alien, don’t ask), The Flash very nearly reintroduced the character in the Arrow-verse with a slight twist. Producers originally thought to feature Carter’s character as the Vice President to Jerry Wasserman’s unnamed POTUS, the disintegration of whom would naturally lead to Marsdin becoming President in either reality.

According to executive producer Marc Guggenheim (via ComicBook), the cameo was ultimately seen as distractingly convoluted:

In the first draft of the script, [Lynda Carter's character] was the vice president who becomes the President, and we got a note from the studio which we think was pretty fair, which was that it was a bit too confusing. You get into the parallel Earths of it all but she’s not the President on our Earth but the Vice President. In the midst of time travel and aliens, it was just one sci-fi problem too much.

That’s certainly understandable, given the burden of setup already imposed on one episode to bring together all-four series against the alien Dominators, even if it did seem notably odd that no one drew much attention to the assassination of a U.S. President. Not for nothing, it might create additional complications whenever Supergirl circles back to its reveal of Marsdin as an alien (or impostor), that fans might wonder the same of her Earth-1 counterpart.

Either way, the remaining two episodes may yet address the political vacuum in the Arrow-verse, so stay tuned for the 100th episode and “Invasion!” continuation tonight.